86You can have the device automatically calculate the default path cost, or you can configure the path costfor ports.Specifying a standard for the device to use when it calculatesthe default path costCAUTION:If you change the standard that the device uses to calculate the default path costs, you restore the pathcosts to the default.You can specify a standard for the device to use in automatic calculation for the default path cost. Thedevice supports the following standards:• dot1d-1998—The device calculates the default path cost for ports based on IEEE 802.1d-1998.• dot1t—The device calculates the default path cost for ports based on IEEE 802.1t.• legacy—The device calculates the default path cost for ports based on a private standard.Table 14 shows the mappings between the link speed and the path cost.Table 14 Mappings between the link speed and the path costLink speed Port type Path costIEEE 802.1d-1998 IEEE 802.1t Private standard0 N/A 65535 200,000,000 200,00010 MbpsSingle port1002,000,000 2000Aggregate interfacecontaining 2 Selected ports 1,000,000 1800Aggregate interfacecontaining 3 Selected ports 666,666 1600Aggregate interfacecontaining 4 Selected ports 500,000 1400100 MbpsSingle port19200,000 200Aggregate interfacecontaining 2 Selected ports 100,000 180Aggregate interfacecontaining 3 Selected ports 66,666 160Aggregate interfacecontaining 4 Selected ports 50,000 1401000 MbpsSingle port420,000 20Aggregate interfacecontaining 2 Selected ports 10,000 18Aggregate interfacecontaining 3 Selected ports 6666 16Aggregate interfacecontaining 4 Selected ports 5000 14
